Work out x. Give reasons for your answer.

The measurement for x is 80°

Step-by-step explanation:

In the picture, we see two parallel lines cut by a transversal line. Since the lines are cut by a transversal, then there are a few things we should know that can help us find the value of x.

Now that we know these things, we can use this information to find the measurement of ∠CBA. We do this by subtracting 100 from 180 because ∠CBA and ∠CBD are a linear pair. Once we know the measurement of this angle, then it will be much easier to find the value of x.

180 - 100 = 80

So, the measurement of ∠CBA is 80°. Now, ∠CBA and ∠x are corresponding angles so this means that they have the same measurements. If the measurement of ∠CBA is 80°, then the measurement of ∠x is also 80°

x = 80°

8(-10x+3.5y-7)

8×-10x + 8×3.5y + 8×-7

-80x + 28y - 56

therefore

-80x+28y-56 is the correct answer